Sense of coherence and substance use in adults: a systematic review and meta-analysis

This study systematically reviews the evidence on the association between sense of coherence (SOC) and substance use during adulthood. Two researchers conducted independent literature searches on the PubMed, LILACS, PsycINFO and Web of Science databases. Original articles assessing SOC and substance use in adults (age > 19 years) were included. Two reviewers independently assessed studies in two phases - initially by reading the title/abstract, then the full text. Discrepancies were resolved by a third reviewer. Estimates were pooled using random-effects models. Bibliographic search identified 21 studies on the association between SOC and substance use in adults. Studies (n = 11) that assessed the association with tobacco smoking found a 0.92 (95%CI: 0.82; 1.01, very low degree of certainty) odds of smoking among those with a high SOC; the association was not modified by age. Individuals with a strong SOC had lower odds of using alcohol (pooled effect: OR = 0.70, 95%CI: 0.50; 0.90, very low degree of certainty); adjustment for confounding variables decreased the magnitude of the association (pooled OR = 0.89, 95%CI: 0.80; 0.98). This systematic review and meta-analysis suggests that a strong SOC protects against substance use among adults regardless of age, with practical implications for preventive interventions and tailored strategies aimed at high-risk individuals. Longitudinal studies are needed to understand the impact of SOC on substance use. Examining interactions with socioeconomic factors and including diverse populations would enhance generalizability.


Rationale
3 Describe the rationale for the review in the context of existing knowledge.
Pg. 1 Objectives 4 Provide an explicit statement of the objective(s) or question(s) the review addresses.

Eligibility criteria 5
Specify the inclusion and exclusion criteria for the review and how studies were grouped for the syntheses.Pg. 2 Information sources 6 Specify all databases, registers, websites, organisations, reference lists and other sources searched or consulted to identify studies.Specify the date when each source was last searched or consulted.

Pg. 2
Search strategy 7 Present the full search strategies for all databases, registers and websites, including any filters and limits used.Suppl.Material 3 Selection process 8 Specify the methods used to decide whether a study met the inclusion criteria of the review, including how many reviewers screened each record and each report retrieved, whether they worked independently, and if applicable, details of automation tools used in the process.

Pg. 2-3
Data collection process 9 Specify the methods used to collect data from reports, including how many reviewers collected data from each report, whether they worked independently, any processes for obtaining or confirming data from study investigators, and if applicable, details of automation tools used in the process.

Data items 10a
List and define all outcomes for which data were sought.Specify whether all results that were compatible with each outcome domain in each study were sought (e.g. for all measures, time points, analyses), and if not, the methods used to decide which results to collect.

Pg. 2 10b
List and define all other variables for which data were sought (e.g.participant and intervention characteristics, funding sources).Describe any assumptions made about any missing or unclear information.

Pg. 3
Study risk of bias assessment 11 Specify the methods used to assess risk of bias in the included studies, including details of the tool(s) used, how many reviewers assessed each study and whether they worked independently, and if applicable, details of automation tools used in the process.

Pg. 3
Effect measures 12 Specify for each outcome the effect measure(s) (e.g.risk ratio, mean difference) used in the synthesis or presentation of results.Pg. 3-4

Synthesis methods 13a
Describe the processes used to decide which studies were eligible for each synthesis (e.g.tabulating the study intervention characteristics and comparing against the planned groups for each synthesis (item #5)).

Did the review authors perform study selection in duplicate?
For Yes, either ONE of the following: □ at least two reviewers independently agreed on selection of eligible studies and achieved consensus on which studies to include □ OR two reviewers selected a sample of eligible studies and achieved good agreement (at least 80 percent), with the remainder selected by one reviewer.

Did the review authors perform data extraction in duplicate?
For Yes, either ONE of the following: □ at least two reviewers achieved consensus on which data to extract from included studies □ OR two reviewers extracted data from a sample of eligible studies and achieved good agreement (at least 80 percent), with the remainder extracted by one reviewer.

Web of Science 180
PsyInfo 168

Did the research questions and inclusion criteria for the review include the components of PICO? 2. Did the report of the review contain an explicit statement that the review methods were established prior to the conduct of the review and did the report justify any significant deviations from the protocol?
16bCite studies that might appear to meet the inclusion criteria, but which were excluded, and explain why they were excluded.Suppl.MaterialStudy characteristics 17Cite each included study and present its characteristics.Suppl.Material 5,6Risk of bias in studies 18 Present assessments of risk of bias for each included study.Suppl.MaterialResults of individual studies 19For all outcomes, present, for each study: (a) summary statistics for each group (where appropriate) and (b) an effect estimate and its precision (e.g.confidence/credible interval), ideally using structured tables or plots.Suppl.Material 5,6Results of syntheses 20aFor each synthesis, briefly summarise the characteristics and risk of bias among contributing studies.Pg. 4 20bPresent results of all statistical syntheses conducted.If metaanalysis was done, present for each the summary estimate and its precision (e.g.confidence/credible interval) and measures of statistical heterogeneity.If comparing groups, describe the direction of the effect.

Did the review authors explain their selection of the study designs for inclusion in the review?
For Yes, the review should satisfy ONE of the following: □ Explanation for including only RCTs □ OR Explanation for including only NRSI □ OR Explanation for including both RCTs and NRSI □ Yes □ No 4. Did the review authors use a comprehensive literature search strategy?For Partial Yes (all the following):

If meta-analysis was performed, did the review authors assess the potential impact of RoB in individual studies on the results of the meta-analysis or other evidence synthesis?
□ included only low risk of bias RCTs □ OR, if the pooled estimate was based on RCTs and/or NRSI at variable RoB, the authors performed analyses to investigate possible impact of RoB on summary estimates of effect.

Did the review authors report any potential sources of conflict of interest, including any funding they received for conducting the review?
□ The authors reported no competing interests OR □ The authors described their funding sources and how they managed potential conflicts of interest

Table S1
Database search strategy on substance use/health risk behaviors.